#include <fstream>
#include <string.h>

using namespace std;

ifstream fin("text.in");
ofstream fout("text.out");

int isLet(char cev){
    return ((cev>='a'&&cev<='z')||(cev>='A'&&cev<='Z'));
}

char ceva[1000001];
int lungimeTot=0, nrCuv=0;

int main()
{
    while(!fin.eof())
    {
        fin.getline(ceva,1000001);
        bool incep=false;
        int lungime = strlen(ceva)
        for(int i = 0;i<lungime;i++)
        {
            if(isLet(ceva[i]))
            {
                lungimeTot++;
                if(incep==false){
                    nrCuv++;
                }
                incep=true;
            }
            else
            {
                incep=false;
            }
        }
    }

    int res = lungimeTot/nrCuv;
    fout<<res;
}